A belowground basement can cut the fallout radiation to one tenth of the outside level. The safest place is the basement corner least exposed to windows and deepest below ground.

If there is time after the warning, the basement shielding could be improved substantially by blocking windows with bricks, dirt, books, magazines, or other heavy material.

Large apartment buildings of masonry or concrete provide better natural shelter than the usual family dwellings. In general, such apartments afford more protection than smaller buildings because their walls are thick and there is more space.

The central area of the ground floor of a heavily constructed apartment building, with concrete floors, should provide more fallout protection than the ordinary basement of a family dwelling. The basement of such an apartment building may provide as much natural protection as the specially constructed concrete block shelter recommended for the basement of a family dwelling.

The Federal Government is aiding local governments in several places to survey residential, commercial and industrial buildings to determine what fallout protection they would provide, and for how many people.

The problem for the city apartment dweller is primarily to plan the use of existing space. Such planning will require the cooperation of other occupants and of the apartment management.